/*字体样式*/
.my_font{
    font-style: italic;
    font-weight:bolder;
    font-size: 2.17em;
    font-family: 华文中宋,Serif;
    line-height: 5rem;/*5px*16=80px*/
    /*line-height:5em;*//* 5*font-size(2.75em)=5 * 2.75*16px=220px*/
}
/*文本样式 */
.my_text{
    border: 1px solid black;
    width: 30rem;
    height: 10rem;
    letter-spacing: 1rem;
    line-height: 2rem;
    text-indent: 1rem;
    vertical-align: middle;
}

/*颜色样式*/
.my_color{
    border: 1px solid black;
    width: 30rem;
    height: 10rem;
    color: blue;
}
/*背景样式*/
.my_bg{
    border: 1px solid black;
    width: 50rem;
    height: 20rem;
    background: #c82333 url("https://www.baidu.com/img/bd_logo1.png")no-repeat left top;
}
/*列表样式*/
.my_list{
    list-style-type: none;
    list-style-image: url("http://www.jju.edu.cn/images/ico1.gif");
}

/*盒子模型*/
.my_box{
    width: 50rem;
    height: 20rem;
    border: 1px solid firebrick;
    margin: 1rem 1rem 1rem 1rem;
    padding: 1rem;
}